Management of cardiopulmonary emergencies in hyperbaric medicine

Introduction

Published data concerning cardiopulmonary emergencies during hyperbaric oxygen therapy (HBOT) are available, however, incidence is unknown [1]. Due to a tremendous increase in the number of HBO treatments throughout Germany since the recent installation of over 60 new hyperbaric institutions (mainly not attached to hospitals) a higher dimension of incidents is presumed. In multiplace hyperbaric chambers up to 12 patients are under video supervision from outside by chamber operators. Some problems arising from emergencies during HBOT are not evident in all situations.

Methods

Video recordings of megacode training sessions with an AMBU^® resuscitation mannequin in a multiplace/multilock hyperbaric chamber (HAUX Starmed^® 2200/5,5) were analyzed. Thereby the particularity of emergency management under hyperbaric conditions was evaluated.

Results

Without attending personnel in the hyperbaric chamber emergency situations will not always be recognized instantly. A further delay of 30-120 s in attending the emergency originates from the need of pressure equalization in the personnel lock. During this maneuver guidance of the patients inside the chamber from outside by the chamber operator is impossible due to increasing noise. Simultaneous surfacing of all chamber occupants is not advisable, but cannot be avoided in some cases to achieve conditions for efficient therapy because of limited space within the chamber. Evacuation of the emergency patient under pressurised conditions into the personnel lock can be facilitated by the use of a dividable stretcher which is stored under the opposite rows of seats in the main compartment.

Conclusion

Algorithms for the management of emergencies under hyperbaric conditions are essential as well as appropriate chamber architecture. Advanced treatment is accomplished after transfer of the emergency patient into the personnel lock, because panic reactions of other patients within the main chamber have to be anticipated. Routine monitoring of ECG, NIBP and tcPO₂ in all patients is mandatory if no personnel is attending inside the chamber during HBOT.